|Pump type and source|Typical use|35 °C (e.g. heated screed floor)|45 °C (e.g. heated screed floor)|55 °C (e.g. heated timber floor)|65 °C (e.g. radiator or DHW)|75 °C (e.g. radiator and DHW)|85 °C (e.g. radiator and DHW)|
|---|---|---|---|---|---|---|---|
|High-efficiency air source heat pump (ASHP), air at −20 °C||2.2|2.0|‐|‐|‐|‐|
|Two-stage ASHP, air at −20 °C|Low source temperature|2.4|2.2|1.9|‐|‐|‐|
|High efficiency ASHP, air at 0 °C|Low output temperature|3.8|2.8|2.2|2.0|‐|‐|
|Prototype transcritical CO 2 (R744) heat pump with tripartite gas cooler, source at 0 °C|High output temperature|3.3|‐|‐|4.2|‐|3.0|
|Ground source heat pump (GSHP), water at 0 °C||5.0|3.7|2.9|2.4|‐|‐|
|GSHP, ground at 10 °C|Low output temperature|7.2|5.0|3.7|2.9|2.4|‐|
|Theoretical Carnot cycle limit, source −20 °C||5.6|4.9|4.4|4.0|3.7|3.4|
|Theoretical Carnot cycle limit, source 0 °C||8.8|7.1|6.0|5.2|4.6|4.2|
|Theoretical Lorentzen cycle limit (CO 2 pump), return fluid 25 °C, source 0 °C||10.1|8.8|7.9|7.1|6.5|6.1|
|Theoretical Carnot cycle limit, source 10 °C||12.3|9.1|7.3|6.1|5.4|4.8|

Question: how many pump types have no typical use listed?
Answer: 6